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elineurycollado
631 PointsThe "Chomp" in my code continues to loop and I don't seem to understand why that is.
It began here:
"while (dispenser.dispense()) { System.out.println("Chomp!") ; }"
When I attempted to bypass this while loop, the same issue occurred with my other while loop a few lines below this initial "Chomp!" while loop.
I don't know exactly why this is occurring and would love some insight from anyone willing to point me in the right direction and attempting to understand where my hiccup occurred.
class PezDispenser {
public static final int MAX_PEZ = 12;
final private String characterName;
private int pezCount;
public PezDispenser(String characterName) {
this.characterName = characterName;
pezCount = 0;
}
public boolean dispense() {
boolean wasDispensed = false;
if (!isEmpty()){
pezCount--;
wasDispensed = true;
}
return wasDispensed;
}
public boolean isEmpty() {
return MAX_PEZ == 0;
}
public String getCharacterName() {
return characterName;
}
public void fill() {
fill(MAX_PEZ);
}
public void fill(int pezAmount) {
pezCount += pezAmount;
}
}
public class Example {
public static void main(String[] args) {
// Your amazing code goes here...
System.out.println("We are making a new PEZ dispenser");
System.out.printf("FUN FACT: There are %d PEZ allowed in every dispenser %n",
PezDispenser.MAX_PEZ);
PezDispenser dispenser = new PezDispenser("Yoda");
System.out.printf("The dispenser is %s %n",
dispenser.getCharacterName());
if (dispenser.isEmpty()) {
System.out.println("Dispenser is Empty");
}
System.out.println("Filling the dispenser with delicious PEZ...");
dispenser.fill();
if (!dispenser.isEmpty()) {
System.out.println("Dispenser is Full");
}
while (dispenser.dispense()) {
System.out.println("Chomp!") ;
}
if (dispenser.isEmpty()) {
System.out.println("Ate all the PEZ");
}
dispenser.fill(4);
dispenser.fill(2);
while(dispenser.dispense()) {
System.out.println("Chomp!!");
}
}
}
I posted the script to hopefully make it easier to point out any blatant issues. Thank you in advance.
1 Answer
Michael Hulet
47,913 PointsThe issue here comes down to your implementation of PezDispenser.isEmpty. To understand this, let's walk through what happens on a single iteration of your loop:
- The loop calls
dispenser.dispense()to see if it should do another iteration - The
dispensemethod makes a variable calledwasDispensedand sets it tofalse - The
ifblock checks the value ofisEmpty()and runs its block if it returnsfalse(normally it would be if it wastrue, but the!inverts the value) -
isEmptychecks to see ifMAX_PEZis equal to0, andreturnstrueif it is, andfalseif it isn't - Since
isEmptyreturnsfalse, theifblock runs - The value of
pezCountis decreased by 1 - The value of
wasDispensedis set totrue -
dispensereturns the value ofwasDispensed, which was just set totrue - Since
dispenser.dispense()returnedtrue, the loop runs
The issue here comes at step 4 in this list. MAX_PEZ is a constant that never changes, and it's set to 12. Since 12 is not equal to 0, isEmpty() will always return false, which means the if block in dispense will always run, and wasDispensed will always be set to true, which means dispense will always return true, so the loop will always run
Based on the context, I think you probably wanted to check to see if pezCount is equal to 0 in isEmpty instead of MAX_PEZ. That way, it starts out with however many it has been filled to have, and the loop will have it count down to 0, which will make isEmpty eventually return true when the PEZ dispenser is empty, and the loop will end
elineurycollado
631 Pointselineurycollado
631 PointsThank you very much, that was what I intended to do (check if pexCount == 0,)!